Lung capillary leak syndrome is a dose limiting toxicity brought about by administration of cytokines, lymphokines, growth factors, recombinant proteins and the like to patients and it produces major morbidity. Lung capillary leak is due to an increase in vascular permeability and is manifested by multi-organ system dysfunction and generalized fluid accumulation and in particular the accumulation of fluid in the lung. Patients with lung capillary leak require respiratory and ventilatory support (see J. P. Siegel and R. K. Puri, Interleukin-2 toxicity, Journal of Clinical Oncology, Vol. 9, pp 694-704, 1991) adding to the expense of medical care. The most troublesome effect of lung capillary leak syndrome is the extravasation of fluid into the lungs, thereby producing interstitial pulmonary edema, often requiring the termination of cytokine, lymphokine, growth factor or protein therapy and the use of supplemental oxygen and other respiratory and ventilatory support measures.
Heretofore, corticosteroids have been utilized to attenuate lung capillary leak syndrome induced by the lymphokine Interleukin-2 (IL-2). However, the corticosteroids adversely affect the antitumor efficacy of the IL-2(Vetto, J. T., M. Z. Papa, M. T. Loitze J. Clin. Oncol. 5:496-503 1987; Papa M. Z., J. T. Vetto, S. E. Ettinghausen, J. J. Mule and S. A. Rosenberg. Cancer Res. 46:5618-5623, 1986).